1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
vichka [17]
2 years ago
8

Select the correct answer. What are the roots of this quadratic equation? 3x^2 + 10 = 4x

Mathematics
1 answer:
Nuetrik [128]2 years ago
8 0
D is the right answer
You might be interested in
As an estimation we are told £3 is €4.<br> Convert £72 to euros.
Luden [163]

(72×4)÷3

Please solve this

Any answer you get is the Answer

4 0
3 years ago
Read 2 more answers
What is the equation of the line that passes through the point (4, 12) and has a y-intercept of -2?
natima [27]

Answer:

The answer is D.

Step-by-step explanation:

:DDDDDDDDD

4 0
3 years ago
What is the slope of the line that passes through these two points?
Dmitry_Shevchenko [17]

Answer:

undefined

Step-by-step explanation:

We can use the slope formula to find the slope

m = ( y2-y1)/(x2-x1)

   = ( 9-3) / ( 2-2)

   = 6/0

When we divide by zero, the result is undefined

This means the slope is undefined

7 0
2 years ago
Let X1 and X2 be independent random variables with mean μand variance σ².
My name is Ann [436]

Answer:

a) E(\hat \theta_1) =\frac{1}{2} [E(X_1) +E(X_2)]= \frac{1}{2} [\mu + \mu] = \mu

So then we conclude that \hat \theta_1 is an unbiased estimator of \mu

E(\hat \theta_2) =\frac{1}{4} [E(X_1) +3E(X_2)]= \frac{1}{4} [\mu + 3\mu] = \mu

So then we conclude that \hat \theta_2 is an unbiased estimator of \mu

b) Var(\hat \theta_1) =\frac{1}{4} [\sigma^2 + \sigma^2 ] =\frac{\sigma^2}{2}

Var(\hat \theta_2) =\frac{1}{16} [\sigma^2 + 9\sigma^2 ] =\frac{5\sigma^2}{8}

Step-by-step explanation:

For this case we know that we have two random variables:

X_1 , X_2 both with mean \mu = \mu and variance \sigma^2

And we define the following estimators:

\hat \theta_1 = \frac{X_1 + X_2}{2}

\hat \theta_2 = \frac{X_1 + 3X_2}{4}

Part a

In order to see if both estimators are unbiased we need to proof if the expected value of the estimators are equal to the real value of the parameter:

E(\hat \theta_i) = \mu , i = 1,2

So let's find the expected values for each estimator:

E(\hat \theta_1) = E(\frac{X_1 +X_2}{2})

Using properties of expected value we have this:

E(\hat \theta_1) =\frac{1}{2} [E(X_1) +E(X_2)]= \frac{1}{2} [\mu + \mu] = \mu

So then we conclude that \hat \theta_1 is an unbiased estimator of \mu

For the second estimator we have:

E(\hat \theta_2) = E(\frac{X_1 + 3X_2}{4})

Using properties of expected value we have this:

E(\hat \theta_2) =\frac{1}{4} [E(X_1) +3E(X_2)]= \frac{1}{4} [\mu + 3\mu] = \mu

So then we conclude that \hat \theta_2 is an unbiased estimator of \mu

Part b

For the variance we need to remember this property: If a is a constant and X a random variable then:

Var(aX) = a^2 Var(X)

For the first estimator we have:

Var(\hat \theta_1) = Var(\frac{X_1 +X_2}{2})

Var(\hat \theta_1) =\frac{1}{4} Var(X_1 +X_2)=\frac{1}{4} [Var(X_1) + Var(X_2) + 2 Cov (X_1 , X_2)]

Since both random variables are independent we know that Cov(X_1, X_2 ) = 0 so then we have:

Var(\hat \theta_1) =\frac{1}{4} [\sigma^2 + \sigma^2 ] =\frac{\sigma^2}{2}

For the second estimator we have:

Var(\hat \theta_2) = Var(\frac{X_1 +3X_2}{4})

Var(\hat \theta_2) =\frac{1}{16} Var(X_1 +3X_2)=\frac{1}{4} [Var(X_1) + Var(3X_2) + 2 Cov (X_1 , 3X_2)]

Since both random variables are independent we know that Cov(X_1, X_2 ) = 0 so then we have:

Var(\hat \theta_2) =\frac{1}{16} [\sigma^2 + 9\sigma^2 ] =\frac{5\sigma^2}{8}

7 0
3 years ago
3. Find the surface area of the figure.<br> 9.4 ft<br> 7 ft<br> 11 ft<br> 15 ft<br> 5 ft
mylen [45]

Answer:

use a caculater mabey

Step-by-step explanati

5 0
2 years ago
Other questions:
  • Help me with this problem like the whole thing
    10·1 answer
  • Lindsay bedford works at a baseball cap shop. she is paid $6.50 per hour plus $0.45 foreach cap she embroiders. how many caps mu
    5·1 answer
  • What is the third step in simplifying this equation (10-7) + (2*14/4)
    14·1 answer
  • What is a common denominator of 1/2 and 1/4
    6·2 answers
  • The set of ordered pairs (1, 7), (3, 8), (3, 6), (6, 5), (2, 11), (1, 4) represents a relation. Is the relation a function?
    12·1 answer
  • The dot plots show rainfall totals for several spring storms in highland areas and lowland areas. What is the median rainfall fo
    8·2 answers
  • Write an exponential function to model the situation. Then find the value of the function after 5 years to the nearest whole num
    14·1 answer
  • The total area of Canada is 9 984 670 km2. Calculate the side length of a square with the same area. Show your work.
    15·1 answer
  • Please Help Will GIve Brainlest! Locks in 1 Hour!
    13·1 answer
  • Find the volume of the figure <br> h=9.5', r=1.8'
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!